Corsair Bikes website update
- Thread starter blue
- Start date
wow...a shock up top, and bellow.
love it, when do they come out?
From reading the website it looks like the secondary shock is just a bottom out to lower the leverage ratio...
Fall 2007
ahh, yes reading...
boo to that reason though. Wouldn't it have been easier to simply design it differently?
That is different with the two rear shocks, have never seen that before.
It's been done a few times. Most succesfully (I think) by http://www.2stagebikes.com/
Im not gana lie...2stage bikes is officially on my list for "bikes I want"
That 2 stage bike is pretty sick looking.
I don't understand the two shock theory with all of today's shocks available. WOuldn't it be better to simply have one shock that is tuned properly and has air assist?? Do you think the two shock frame works better than a well designed frame with a double barrel??
Well, I mean 240mm of travel...that's what, 9.5 inches? I think it's to lower the leverage ratio for better quality travel and to be easier on the shock(s). The site does say you can run it in seven or eight inch mode w/o the secondary shock. To get that much travel with a normal MTB sized-shock you get high leverage ratios. What is the V10s?
That frame would look schwing with a Boxxer WC on it...
That frame would look schwing with a Boxxer WC on it...
yeah, 9.5" would require a 4" or longer stroke (longest I have seen is 3.5" Roco and Fox) if you wanted to keep the leverage low. Otherwise you're looking at 3:1. I don't really know how the second shock affects the leverage ratios, though. Do you just add the strokes of both shocks together?
i'd just love to see somebody design a dual shock to have a travel area, vertical and back. Nobody seems to want to do it, everybody's all "stable platform" or "air assist" or don't design it right. Even sinister couldn't make it work, number one, and if they had, it would have had limited travel in it's upper rear position (because of running one shock) and that's where you need the most travel.
these guys are real close, but I wish the main pivot were higher. I think if you tuned both shock soft enough you could get the travel area...
these guys are real close, but I wish the main pivot were higher. I think if you tuned both shock soft enough you could get the travel area...
Who say's Sinister can't make it work? From what I hear it's a priority r&d project for as soon as possible release.
ive got three questions, one is about the idler pulley the site mentions, cant see it and why does it have one? where is it fastened?
second is, is there a mechanical stop that makes the shocks work in series, or is this a 2 DOF system with area travel?
third: am i seeing a concentric secondary pivot?
second is, is there a mechanical stop that makes the shocks work in series, or is this a 2 DOF system with area travel?
third: am i seeing a concentric secondary pivot?
i'm stoked to see some of the tube formation and the general asthetics of the bikes, hopefully it is reflected by what is to come as well. honestly though, i'm disappointed with the frame. sure, they did some awesome design work, but i just think that there would have been a better way to come out onto the market. it is essentially a single pivot with an addition back up shock thrown in. it's unique, but it has been done, and the design isn't all that fabulous. it basically adds a vertical piece to the wheelpath at the end of the stroke. i love the looks, but i won't be buying one.
Well it says they are going to release 6 frames I only see 4 on their site so there are two more coming still
It is definitely not just a single pivot. You cannot get a multi directional axle path out of a single pivot. The animation clearly shows the axle path moving in two distinct stages.
Really, by who? Serious question.
Actually it seems to follow a close to vertical path up though the first 7" of travel, then moves sharply rearward through the last 2 1/2". This makes good sense to me as the bike would maintain a shorter wheelbase for turning and less dramatic hits enabling better handling, and lengthen to become more stable on large hits and landings.
the only thing what makes me wonder is:
is the coil-shock working as a second link in the last inches of the travel?
that can't be good for the shock...
is the coil-shock working as a second link in the last inches of the travel?
that can't be good for the shock...
Here's something uncool,
In that picture, they've lost the new lower design which positioned the axle directly in front of (and further up) the lowers like all the other forks. Crowns that drop slightly aren't an issue, you'll notice boxxers do it and they are lower than 06/07 888's by about 10mm, as well as having 3mm more travel (ie: much lower). It's that axle positioning you need to be looking at if you're concerned about axle-to-crown height on an 888.
But my guess is that the fork picture corsair have used is an old one, ie probably dated/inaccurate (at least I hope so) - compare it with those leaked 08 marzocchi pictures and you'll notice things don't quite match up.
Really, by who? Serious question.
Karpiel, Kenisis, and I think BCD has done a dual rear shock frame
Karpiel, Kenisis, and I think BCD has done a dual rear shock frame
Any price rumours yet?
well i think price will be similar to intense and brand like this...
they delayed it another year, haven't taken into account brake jack or pedal lockout, and haven't said anything about it since they said they weren't producing it this year.
Cannondale, 2stage, and BCD have all done bikes like this, with 2stage arguably being the most successful.
throw 2stage in there too. maybe the wheelpath hasn't ever been exactly duplicated, but the design is definitely not original. i also recall a smaller german company having something, i'll dig around for it.
as for "not being a single pivot", it may not be in the last bit of the stroke when that second shock is engaged, but it is certainly a single pivot in the beginning. go to the site and drag the little grey cursor up through the travel. the suspension is rotating around on one pivot only, a quality single pivots are known to have. i'd like to make it so i can draw the wheelpath, but i don't know how. anyways, it remains in single pivot mode until it uses all of the travel and the little air shock engages. then the wheelpath turns vertical. this makes sense as well, and with the use of their special chain guide that they are going to use, it could make it handle fairly well. hopefully they will be using a design that will counteract the bad pedal feedback that single pivots have. in that case, the bike will still have the great square edged bump compliance that single pivots have. the wheelbase will be slightly lengthening nontheless, but because of that, it will be more stable as the hits start getting bigger. the wheelbase will reach a maximum length at the point the first shock bottoms out, and then the air shock will send the wheel into a vertical path, maintaining the long wheelbase for stability but changing the wheelpath into a vertical one. ever done a big drop on a horst link bike versus a single pivot? horst link frames feel much more under control absorbing that force because it travels in line with the wheelpath.
Is this kind of like the Karpy Poxiclipse?
I'm intrigued by the design, particularly the fact that in the animation it acts like a conventional single pivot till the blow off shock is activated - then the wheelbase lengthens by 2 inches. I wonder what this would feel/ride like?
I like the look of it, but I would also question why not use 1 3.5" stroker? You could still run a leverage ratio of 1/2.7? Not dissing - just want to see what the rationale/performance is like.
Another bike that used a similar design was the Kestrel in the mid 90's. 2 Risse air shocks I believe...
I'm intrigued by the design, particularly the fact that in the animation it acts like a conventional single pivot till the blow off shock is activated - then the wheelbase lengthens by 2 inches. I wonder what this would feel/ride like?
I like the look of it, but I would also question why not use 1 3.5" stroker? You could still run a leverage ratio of 1/2.7? Not dissing - just want to see what the rationale/performance is like.
Another bike that used a similar design was the Kestrel in the mid 90's. 2 Risse air shocks I believe...
no, the karpocalypse used the same end result but different execution. The air shock on that bike was used only as a bottom out, as it was mounted on the back side of a linkage. It was designed to run a high leverage ratio (or is it low?) so that the shock would be ultra-stiff for bender-style maneuvers. It had no split axle path.
the kestrel rubicon was a single pivot that used two shocks, but not even close to either of these bikes. Picture a turner RFX with a shock going to the walking beam link and one in it's normal place. That was basically the idea of the Rubicon. One shock for 4", two for 7.6'. They added a "feature" where if you put pressure on the saddle, the pivot point would change slightly, so when you stood up, the leverage ratio would lower and it would stiffen. Really neat idea, and ellegant execution, but when it get bumpy most people stand...so it was kind of less-than-excellent for most riding.
the kestrel rubicon was a single pivot that used two shocks, but not even close to either of these bikes. Picture a turner RFX with a shock going to the walking beam link and one in it's normal place. That was basically the idea of the Rubicon. One shock for 4", two for 7.6'. They added a "feature" where if you put pressure on the saddle, the pivot point would change slightly, so when you stood up, the leverage ratio would lower and it would stiffen. Really neat idea, and ellegant execution, but when it get bumpy most people stand...so it was kind of less-than-excellent for most riding.
Ah...I stand corrected. Thanks for setting me straight!
Well, delaying production and continuing to do r&d would indicate that Sinister feels they can make the Passion work, but they don't want to use consumers as a test bed. That is good business.
As for "brake jack and "pedal lockout", if the design does exhibit those characteristics, they can be minimized or eliminated in a number of ways, including floating arms and replacement of the travel "area".
Since when do pedal feedback and square edge bump compliance have anything to do with number of pivots?
Unless there is some sort of bumper in place (which I don't believe could be the case; there has to be movement between the swingarm and the secondary shock driving link for the suspension to work) the only thing causing the design to follow the described wheelpath would be the fact that the secondary shock would have a higher spring-rate than the primary. But this could be overcome depending upon the severity and direction of the hit...
I am confused how the design is able to work with the "blow off" shock removed. Looks like the shock would have to be replaced with a bolt where the shock eye was??
I know you just like to argue, but I'll play ball.
The sinister proto had none of those methods for chain tug. If the rear wheel moves backwards, there is going to be force felt on the pedals, whether it from a high pivot or rearward linkage. I'm surprised and disappointed that sinister didn't design one into their original, but everybody is too busy blowing the guys at sinister to notice.
It's good business to not release something until it's ready, sure. But why isn't it ready now? That's like saying Honda is doing good business by not selling the RN01G until...whenever. We know the bike works, it's worked since they came out with it. They're just dicking with us until they know the market is big enough. I'm not accusing sinister of geurilla marketing, but regardless they can't bring the bike to market for a reason, and it's not for my benefit, it's because they can't get the bike to work the way they want it to, right now. Maybe they'll come up with a redesign or do whatever they need to, but if they had it right the first time, it wouldn't be a problem. Unless they're waiting to release it against a competitor, which is neither here nor there.
How do you replace a travel "area"? Are you talking about an Idrive or similar contraption (glorified URT)? Fact is that as the rear wheel moves backwards, the pedals want it to go forwards, and the sinister design ignored that. It's only an inch or two, but if there's any rearward sag or if you're pedalling over bumps, you're going to inchworm the whole way.
Sinister who?
it is a key problem with the single pivot design. single pivots work better on square edged hits than a bike with a vertical wheelpath because the rear wheel is allowed to move backwards and up. this, however, increases tension on the chain and causes pedal feedback. a single pivot can't achieve a vertical wheel path, which is why the horst link was made. it allows for a vertical path that doesn't result in chain growth, but because the wheelpath is vertical, square edged bump compliance is compromised. rather than being able to move backwards and up to minimize the slowing effects of the bump, the bike just slams into it, and more momentum is taken away.